‘‘I’m fine, I’m fine,’’ Harbaugh said. ‘‘No limits. Going about everything as normal. Had a little irregular heartbeat. I’ve had that before. Now that I have the procedure, a cardiovert, it’s amazing. It gets the heart rate back to normal. Atrial flutter is something I’ve had for a while, most of my life.’’

The reigning NFL Coach of the Year returned to the field to lead San Francisco through a morning walkthrough session, with a full practice scheduled for the afternoon.

‘‘It was pretty cool to see him,’’ safety Donte Whitner said. ‘‘We knew it was a minor heart thing, but a heart thing no matter if it’s minor, it’s serious. It felt a little different without him. Hopefully, he doesn’t have to go through it again.’’

Harbaugh, 48, was away from the team Thursday for his procedure at Stanford Hospital after undergoing tests Wednesday night.

QBs Cutler, Vick out

Jay Cutler will miss Monday’s game at San Francisco because of a concussion, leaving the Bears without their starting quarterback. The team announced the decision Friday, meaning Jason Campbell is the likely starter. The Bears believe Cutler was injured on a helmet-to-helmet hit Sunday night by the Texans’ Tim Dobbins, who was fined $30,000 by the league, late in the second quarter. The 49ers, meanwhile, could be without their starting quarterback, Alex Smith, who suffered a concussion of his own last week . . . Eagles quarterback Michael Vick will miss Sunday’s game against the Redskins because of the effects of a concussion. Rookie Nick Foles, who replaced Vick during the 38-23 loss to Dallas on Sunday, and who practiced with the first team all week, will get his first NFL start in a battle of 3-6 teams fighting to save their seasons. Foles was 22 of 32 for 219 yards with a touchdown and an interception against the Cowboys.

Mendenhall to return

Insisting he feels good with no setbacks after a full week of practice, running back Rashard Mendenhall is set to return for the Steelers. Because of an Achilles’ injury, Mendenhall has missed all four games of a winning streak that the Steelers (6-3) carry into their Sunday showdown with the Ravens (7-2). Mendenhall had not been through a full practice in more than a month . . . Receiver Julio Jones is listed as questionable for the Falcons’ game against the Cardinals after suffering a sprained right ankle in last week’s loss at New Orleans . . . Injured Dallas running back DeMarco Murray is unlikely to return from a four-game absence Sunday against Cleveland while he continues to recover from a sprained right foot . . . Former Bears coach and Hall of Fame player Mike Ditka was hospitalized after suffering what he said doctors told him was a “very minor stroke.” . . . For one week at least, the Bills’ high-priced, much-maligned defense wasn’t missing in action. Mario Williams — Buffalo’s $100 million defensive end — had one of the team’s three sacks, and safety Jairus Byrd recovered a fumble and had an interception in a much-needed, stifling performance that produced a 19-14 win over the visiting Dolphins Thursday night . . . Jaguars defensive tackle Terrance Knighton and Chiefs linebacker Tamba Hali were docked $25,000 each by the NFL for hits on quarterbacks in last week’s games. Oakland linebacker Aaron Curry was given two fines: $15,750 for striking Ravens running back Ray Rice late, and $7,875 for unnecessary roughness on a special teams play. In all, 17 players drew fines for their actions in Week 10.